A vaccine which protects infants against four types of meningitis has shown promise in clinical trials.

Current vaccines against A, C, W-135 and Y strains do not work in children under the age of two years.

But data presented at the World Society for Pediatric Infectious Diseases Congress suggests the new vaccine is protective from six months.

Infants in North America, Africa and Eastern Europe would benefit most from the vaccine, said experts.

Most cases of meningitis in the UK are caused by meningitis C or B.

A vaccine that protects against any cases is worth having, although vaccination policy will vary by country depending on which strains are most common

Dr Andrew Pollard, Sheffield University

The government introduced a vaccine against meningitis C in 1999 and a vaccine against meningitis B - which causes the majority of cases in the UK - is being trialled.

But in other areas of the world, different strains of the infection are more common.

Meningitis A causes deadly epidemics every year in the African "meningitis belt" - an area that stretches from Senegal in the west to Ethiopia in the east.

Strain A is also increasing in Eastern Europe and strain Y is becoming more common in North America.

Immune response

A phase II study of the new vaccine, Menveo, which has been developed by Novartis, found good immune responses in 175 infants who received either two doses at ages six and 12 months or one dose at 12 months against all four strains.

It is a conjugate vaccine, which is better at producing "immune memory" than the older polysaccharide vaccines.

In the vaccine, molecules from the outer membrane of the meningitis virus are attached to a protein which can prompt a stronger immune response than the membrane molecules alone.

It is currently being assessed in larger trials and is expected to be submitted for regulatory approval next year.

In June, the Meningitis Vaccine Project, announced successful results in Africa with trials of a conjugate meningitis A vaccine.

Further studies are planned in India and in Burkina Faso in Africa. If successful authorities then plan to introduce the vaccine across the rest of West Africa at a cost of about 40 US cents per dose.

Dr Andrew Pollard, head of the Paediatric Infection and Immunity Laboratory at the University of Oxford, said strains of meningitis varied from country to country.

He added most cases in the UK are now caused by group B, but around 50-183 cases a year were caused by strains other than B and C, mainly types W-135 or Y.

"A vaccine that protects against any cases is worth having, although vaccination policy will vary by country depending on which strains are most common."

Chris Head, chief executive of the Meningitis Research Foundation said current vaccines against A, W-135 and Y strains provided limited protection in the very young.

"The prospect of broader protection against meningitis and septicaemia is tremendously encouraging, particularly for young children who bear the greatest burden from these deadly diseases."

Professor Robert Read, an expert in infectious diseases at the University of Sheffield said the vaccine could be very useful in parts of Africa where they get large outbreaks of meningitis A but also meningitis W-135.

"The attack rate can be upwards of one per 1000 so your chance of getting meningitis as a baby is incredibly high.